[Sports Performance] NSCA -National Strength & Conditioning Association, Jay Dawes, Mark Roozen - Developing Agility and Quickness (2011, Human Kinetics)

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Developing Agility
and Quickness
Human Kinetics
National Strength and 
Conditioning Association
Jay Dawes
Mark Roozen
EDitoRS
Library of Congress Cataloging-in-Publication Data
 Developing agility and quickness / Jay Dawes, Mark Roozen, editors.
 p. cm.
 Includes bibliographical references and index.
 ISBN-13: 978-0-7360-8326-3 (soft cover)
 ISBN-10: 0-7360-8326-X (soft cover)
 1. Sports sciences. 2. Sports--Physiological aspects. 3. Motor ability. 4. Motor learning. I. Dawes, 
Jay. II. Roozen, Mark, 1961- III. National Strength & Conditioning Association (U.S.) 
 GV558.D45 2011
 613.71--dc23
 2011025357
ISBN-10: 0-7360-8326-X (print)
ISBN-13: 978-0-7360-8326-3 (print)
Copyright © 2012 by National Strength and Conditioning Association
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E4818
Developing Agility
and Quickness
iv
Factors Determining Agility . . . . . 1
Factors Determining 
Quickness . . . . . . . . . . . . . . . . . . 25
Testing Agility and Quickness . . 35
Agility Drills . . . . . . . . . . . . . . . . . . . 55
Quickness Drills . . . . . . . . . . . . . . . 93
Contents
Introduction vii
Key to Diagrams xi
1
2
3
4
5
	 v
Agility and Quickness Program 
Design . . . . . . . . . . . . . . . . . . . . 115
Sport-Specific Agility and 
Quickness Training . . . . . . . . . 127
References 161
Index 173
About the NSCA 179
About the Editors 181
About the Contributors 183
6
7
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	 vii
Introduction
For all athletes, the ability to quickly change direction is often the differ-ence between success and failure. Virtually all sports involve whole-body movements that require athletes to rapidly and instantly accelerate, 
decelerate, or change direction in response to game situations. The reality is 
that in most sports, the ability to quickly change direction is more impor-
tant than great straight-line sprinting speed. For this reason, many coaches 
and athletes are interested in finding effective ways to improve agility and 
quickness. The purpose of this book is to assist sports coaches, athletes, and 
strength and conditioning professionals in accomplishing this goal.
In 2002, Young, Jones, and Montgomery attempted to identify the most 
significant factors influencing agility performance. In particular, these authors 
divided agility performance variables into two main areas: change of direction 
speed and perceptual and decision-making factors.7 Within these two main 
components, several subcomponents exist, as outlined in figure 1. Agility and 
quickness are complex sporting skills that include both physical and cognitive 
components.1, 2, 3, 4, 5, 6, 7 An example is a kick or punt returner in American 
football waiting patiently to receive a ball who must immediately decide 
which way to maneuver through the defense to gain yardage. Or, imagine 
a point guard who dribbles down the lane and must determine whether to 
continue dribbling, pass the ball, or shoot. These are prime examples of how 
athletes must move and think fast to achieve lightning quickness on the field 
or court. Therefore, to maximize performance, athletic training programs 
must address both the physical and cognitive components of agility and 
quickness. Only then will athletes be able to truly bridge the gap between 
practice and competition.
Chapter 1 discusses factors that influence agility, such as change-of-
direction speed, proper technique, body position, and physical attributes. It 
also covers the essential components of developing rapid force, high power 
output, and explosive movement, as well as how these fundamental attributes 
influence athletes’ ability to achieve high-level performance.
Chapter 2 explores perceptual and decision-making skills (i.e., quickness 
factors), such as information processing, knowledge of situations, anticipation, 
and arousal and anxiety levels. Athletes with high-level agility performance 
are better at recognizing and capitalizing on task- and game-relevant cues 
that give them a competitive advantage over their opponents. In many cases, 
these skills separate elite performers from everyone else.
Agility
Perception and
decision making
Visual
scanning
Pattern
recognition
Anticipation Knowledge
of situations
Technique
Straight
sprinting
speed
Foot
placement
Adjustment
of strides
to accelerate
and decelerate
Body
lean and
posture
Strength Power
Reactive
strength
Leg
muscle
qualities
Anthropometric
variables
Change of
direction speed
E4818/NSCA/Fig Intro F/412898/Tammy Page/R1
viii	 ■ Introduction
As with any training program, athletes must be physically prepared for 
the demands of training. Agility and quickness training is no different. 
Therefore, prior to the chapters with specific drills to enhance agility and 
quickness (chapters 4 and 5), chapter 3 discusses techniques to evaluate an 
athlete’s readiness in detail. This chapter also presents methods for monitor-
ing athletes’ progress with both qualitative-movement assessments and tests 
that predict agility performance.
Chapters 4 and 5 present a wide variety of drills to improve agility and 
quickness. Many of these drills develop general motor programs and improve 
fundamental movement skills for future athletic success. These chapters also 
include suggestions
and specific training drills that incorporate cognitive 
Figure 1 Components of agility.
Adapted, by permission, from W.B. Young, R. James, and I. Montgomery, 2002, “Is muscle 
power related to running speed with changes of direction?” Journal of Sports Medicine and 
Physical Fitness 42(3):282-288.
Introduction ■ ix
decision-making tasks into athletes’ training programs once they have 
mastered the techniques. These unplanned, or open, drills require athletes 
to process information from the environment and to respond quickly with 
accuracy and precision.
The selected drills provide a solid base of information to assist in the develop - 
ment of athlete-specific and sport-specific training programs. Chapter 6 
explores the basic foundations of designing agility and quickness programs. In 
chapter 7, professionals from a variety of sports share their personal philoso-
phies on agility and quickness training and their favorite drills for improving 
sport performance at a variety of skill levels. The drills in this chapter add 
sport-specific training stimulus to the program, which better prepares athletes 
for the chaotic nature of sport and competition.
This book serves as a basic guide and resource for the safe and effective 
development of comprehensive training programs for agility and quickness. 
It is an absolute must-have resource for coaches and athletes who are seri-
ous about taking performance to the next level. It is loaded with invaluable 
training tips and information that the experts in this book have taken a life-
time to develop. The authors hope that athletes, coaches, and performance 
enthusiasts will gain an appreciation and a better understanding of what it 
takes to improve agility and quickness. Excellence is not an accident!
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	 xi
21
Step with left foot
Step with right foot
Numbers indicate order of steps
Foot touch or tap (no weight transfer)
Cone
Sprint
Side shuffle
Backpedal
Bear crawl
Carioca
Defensive player or any player
Offensive player
E4818/NSCA/KTD/413039/Tammy Page/R3-kh
Key to Diagrams
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	 1
Factors Determining 
Agility
ChApter 1
Mark roozen
David N. Suprak
Most team sports, such as basketball, American football, and soccer, are characterized by rapid acceleration, deceleration, and changes of direction within a 10-yard (9 m) window.45 Furthermore, court 
sports, like tennis and volleyball, also require multidirectional first-step quick-
ness and changes of direction within a 4- to 10-meter (4–11 yard) span.40 
According to numerous coaches and sport scientists, an agility task is a rapid, 
whole-body change of direction or speed in response to a stimulus.41, 53 Agility 
can be broken down into subcomponents made up of both physical quali-
ties and cognitive abilities.53 This chapter examines the physical qualities of 
speed, strength, power, and technique, as well as the qualities of leg muscles.
Speed
Athletes who can move faster than their opponents have an advantage. For 
example, a faster athlete may be able to get to a ball more quickly than a 
competitor or may even outrun a pursuer. For this reason, athletes in most 
sports value speed highly. Speed is often measured by using linear (straight-
line) sprinting over a distance between 40 and 100 yards (37–91 m). However, 
it is important to remember that in most sports, athletes rarely sprint more 
than 30 yards (27 m) in a straight line before they must make some type of 
directional change. Unless an athlete is a 100-meter sprinter, focusing a great 
deal of time and attention on straight-ahead speed may not result in optimum 
performance. On the other hand, since most sports require acceleration from 
a static state or when transitioning between movements, straight-line speed 
is still a valuable asset that athletes should focus on when testing and train-
ing for sports.
2	 ■ Developing Agility and Quickness
Linear sprinting is a physical skill that most people have performed since 
their second year of life with some level of proficiency.22 For decades, many 
coaches believed that linear speed was mostly related to genetics and could 
not be significantly improved by training. However, appropriate training does 
improve running speed, even at the elite level. The combination of stride 
rate (the number of strides per unit of time) and stride length (the distance 
covered in a single stride) primarily determines linear speed. So, athletes 
can improve linear speed by increasing stride rate while maintaining stride 
length, increasing stride length while maintaining stride rate, or doing a 
combination of both.
Most sports, with the exception of track-and-field sprinting, involve short 
sprints (<30 yards) and rapid changes of direction, followed by rapid accel-
erations. For this reason, it makes little sense to focus a large proportion of 
training time on improving speed capabilities for athletes who will rarely 
reach maximum speed in competition. It makes more sense for these athletes 
to focus their attention on training to accelerate.33 Acceleration is the rate of 
change in velocity, so this phase of sprinting is critical for changing directions 
as rapidly and efficiently as possible.
Optimal technique for linear sprinting in the acceleration phase involves 
four factors that maximize stride length and frequency:34
Derrick Rose accelerates past an opponent.
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	 Factors Determining Agility ■ 3
	 1. The body should have a pronounced forward lean that results in a lower 
center of mass. Consequently, momentum in a linear direction increases. 
This position initiates foot contact with the ground under or slightly 
behind the center of mass, reducing forces that cause an athlete to slow 
down or brake.38
	 2. When pushing off the ground during the propulsion phase, the foot 
touches the ground in a cocked position, with the ankle flexed upward 
at approximately 90 degrees (dorsiflexion) and the toes pointed back 
toward the shin. Once the foot makes contact with the ground, the athlete 
extends the hip, knee, and ankle simultaneously with as much force as 
possible (see figure 1.1). This movement is known as triple extension.47
	 3. During the recovery phase, the ankle of the free leg should be dorsiflexed 
while the knee and hip are bent, or flexed. This allows the foot to pass 
directly under the buttocks and a more rapid turnover at the hip.
	 4. The athlete should make certain to initiate arm swing at the shoulder 
with the elbow flexed to 90 degrees. He should work on swinging the 
arm forcefully backward to let the body’s stored elastic energy and stretch 
reflex provide much of the arm’s forward propulsion.10
Figure 1.1 Proper technique for straight-
ahead sprinting.
4	 ■ Developing Agility and Quickness
In the propulsion phase, the power output and rate of force development 
of the muscles that make up the hip extensors and the quadriceps muscles 
contribute to both stride length and frequency.20 In the recovery phase of the 
sprint, the hip flexor muscles (located on the front side of the hip) and the 
hamstring muscles (located on the backside of the upper thigh) are the major 
contributors to stride frequency. The strength and power of the hip flexors 
are important factors in rotating the hip quickly from an extended position 
to a flexed position in preparation for subsequent foot contact.
The hamstrings have an important role as a multijoint muscle group. 
Because the hamstring muscles cross over both the hip and the knee, they 
are responsible for slowing down, or decelerating, the lower leg during the 
recovery phase in preparation for contact with the ground. At the same time, 
they also immediately
transition to help the hip extend for the propulsion 
phase of sprinting.55
In contrast to straight-ahead sprinting, during backpedaling, the ham-
string muscles are less active and the quadriceps muscles are more active.15 
Lateral movements involve more activity from the hip abductors than forward 
sprinting does. These muscles take the leg away from the body. Therefore, 
programs focused on improving agility performance should pay particular 
attention to developing strength in the hip flexors, the hamstrings, and the 
muscles that surround the hips.
Another important factor contributing to optimum speed is joint flexibility. 
If the hamstrings are excessively tight, athletes may not be able to bring the 
knee up as high during the recovery phase of sprinting, hindering hip flexion 
and speed. Furthermore, tight hip flexors may restrict the ability to extend 
the hip through the full necessary range of motion, thereby reducing power 
output during the triple-extension phase of propulsion. Proper flexibility of 
the involved joints contributes to movements that are more fluid and coor-
dinated, resulting in longer and faster strides and greater speed.
Strength
Strength is the maximum force that a muscle or muscle group can generate.27 
In most activities, athletes are unable to reach their optimal strength levels 
because of the speed at which they are moving. Strength is important, but so 
is the ability to use that strength to generate force. Force is calculated with 
the following equation:
Force = Mass × Acceleration
Therefore, force can be altered by increasing the mass of the object 
being moved, increasing the acceleration of a given object’s mass, or with a 
	 Factors Determining Agility ■ 5
combination of both. Often coaches and athletes increase mass to improve 
force. However, as mass increases, or as weight is gained, athletes must be 
sure to maintain their ability to accelerate or move quickly. Gaining weight, 
even if it is lean mass, does not necessarily improve performance if it causes 
the athlete to lose a significant amount of speed.
Strength is an important contributor to agility and to athletic success. In 
agility development, increasing force to move the body more quickly relates 
directly to strength. Therefore, relative strength (strength in relation to body 
mass) is more important than absolute strength (the ability to move a given 
resistance regardless of body weight or mass). Important aspects of strength to 
consider when designing a program for improving agility include concentric, 
eccentric, and stabilization strength.
Concentric Strength
Concentric strength refers to the force exerted by a muscle as it shortens. Think 
of doing a biceps curl and bringing the weight upward. Lifting the weight 
requires a concentric movement of the biceps. Positive work (the force exerted 
against external resistance results in joint movement in the same direction as 
the force or in the opposite direction of the external resistance) also character-
izes concentric muscle actions. An example is the push-off during a running, 
jumping, or cutting movement that is followed by powerful extension of the 
hip, knee, and ankle (this is triple extension; refer to figure 1.1 on page 3). 
Here, gravity works on the body to pull it down. However, with a powerful 
extension (straightening the ankles, knees, and hips), athletes can overcome 
the force of gravity and can more effectively run forward, jump, or make a 
cut. This will help them improve performance levels.
Theoretically, the more force the foot exerts against the ground during 
running or jumping, the greater the acceleration of the body mass will be. 
Likewise, the greater the force developed by the hip flexors during the recovery 
phase of running, the greater the forward acceleration from the hip. Increased 
force from the hip flexors also allows the athlete to position the foot more 
quickly for contact with the ground. This results in greater stride frequency 
during straight-line sprinting and directional changes.13
Scientific literature demonstrates a strong relationship between muscular 
strength and explosive movements, such as vertical8 and horizontal jumping,28 
sprinting,52 and agility37 movements. The relationship between concentric 
strength and explosive movements is even more pronounced when relative 
strength is considered. Relative strength factors in the size and weight of 
an athlete. With absolute strength, if two athletes both squat 300 pounds 
(136 kg), they have the same maximum lift. If one of the athletes weighs 
6	 ■ Developing Agility and Quickness
150 pounds (68 kg) and the other weighs 275 pounds (125 kg), the lighter 
athlete’s relative strength is much greater than the teammate’s. The heavier 
athlete would need to improve relative strength in order to be more explosive.
However, the relationship between concentric strength and explosive 
movements becomes less apparent when considering elite level athletes.54 This 
suggests a threshold in strength at which further improvements in explosive 
movement performance are more closely related to the rate of force develop-
ment (or in other words, the speed at which the necessary amount of force 
can be produced). Maximum concentric strength is especially important in 
the acceleration phase of sprinting.52 Since acceleration is an integral factor 
in optimal agility technique, the role of concentric strength in maximizing 
agility performance is critical.
eccentric Strength
Eccentric strength refers to the force exerted by a muscle as it lengthens. 
Negative work (the force exerted against external resistance results in joint 
movement in the opposite direction of the force or in the same direction as the 
external resistance) characterizes eccentric muscle actions. A simple example 
is lowering the weight back to the starting position during a biceps curl.
An athlete with high eccentric strength can quickly and effectively deceler-
ate his body while maintaining dynamic balance in preparation for a direc-
tional change. The ability to decelerate the body quickly and with control is 
another important contributor to movements that involve rapid directional 
changes. Inadequate eccentric strength can slow deceleration and reduce 
the ability to quickly change direction. The relationship between eccentric 
strength and the ability to decelerate is exemplified by the movements in 
a stretch-shortening cycle (see page 11). In order to minimize contact time 
with the ground during a stretch-shortening cycle (and during agility-type 
movements), adequate eccentric strength is crucial for decelerating the body 
mass quickly so it can be accelerated in a new direction.
The ability to decelerate is important for both performance and for injury 
prevention. Athletes can attain the greatest amount of force during eccentric 
muscle action.21 Most injuries occur during joint deceleration.16 One of the 
main contributors to proper deceleration is eccentric strength of the involved 
musculature. If these structures are not strong enough to withstand force 
during movement, poor body mechanics can lead to improper body position, 
increasing the chance of injury. However, resistance and plyometric training 
of the eccentric strength allows athletes to augment their ability to decelerate 
body mass. This can translate into improved agility and athletic performance.
	 Factors Determining Agility ■ 7
Stabilization Strength
Joint stability is an important and often overlooked factor that contributes to 
the effective application of force during agility movements. Agility training 
requires strengthening the muscles involved in stabilizing the trunk and the 
joints of the lower extremities. For example, when the foot touches the ground 
during a plant-and-cut movement, forces from the ground are transmitted
up through the legs, hips, and trunk. If the musculature surrounding these 
joints and supporting the trunk are not stabilized by muscular contraction, 
then too much force may be absorbed or lost at these locations, slowing the 
transition from eccentric to concentric movements. This results in slow, inef-
ficient movements and less than optimal skill performance.
An example of this is running a multidirectional cone-agility drill. If, due 
to inadequate core stability, an athlete lacks the ability to decelerate lateral 
forces when performing a cutting motion, he will take much longer to make 
a directional change. This potentially elevates the athlete’s risk of injury. If a 
similar athlete who has the ability to stabilize the body and effectively change 
directions were to perform this same action, he may ultimately experience 
higher success and fewer injuries due to his movement proficiency, even if 
he were slightly slower.
Strength that optimizes stabilization is also important for muscle balance. 
For example, during hip extension in the push-off portion of sprinting, the 
gluteus maximus must contract to create the explosive movement that propels 
the body forward. However, the gluteus maximus also helps rotate the hip 
outward. Lack of control of this extraneous movement inhibits athletes’ ability 
to propel themselves forward. To resist unwanted movement at the hip, the 
adductor magnus (a hip adductor that brings the leg back toward the body) 
must contract to improve the stability of the hip joint. This ensures that the 
force created by the gluteus maximus is used for forward propulsion of the 
body and is not wasted on other movements.48
In addition, the medial hamstrings (semimembranosus, located on the back 
portion of the upper thigh) and the lateral gastrocnemius muscles (located on 
the outside portion of the calves) aid in controlling undesirable movement at 
the knee joint during cutting maneuvers.24 Both enhance the performance of 
these movements and reduce the risk for injury.31
Resistance-training exercises can enhance the strength and timing of the 
muscles’ stabilizing contributions, including both bilateral (both sides) and 
unilateral (one side) drills, such as the following:9, 23, 36
ff Multijoint movements, such as the back squat and forward, backward, 
and diagonal lunges
8	 ■ Developing Agility and Quickness
ff Single-limb training, such as single-leg squats and other single-leg 
movements
ff Explosive plyometric movements performed with correct technique, 
such as single-leg bounding and single-leg hops
Intermuscular coordination is another important aspect of muscular con-
traction that is closely related to stability during movement. Each muscle can 
send signals and information to other muscles in the system. The ease and 
speed at which they communicate relates to the activation timing of various 
muscles across a joint. Intermuscular coordination is important for running 
speed because if the hamstrings are not relaxed when the thigh is brought 
forward in the recovery phase of the stride, hip flexion will be reduced, 
resulting in a shorter stride length. This is especially clear in movements 
involving directional changes, where joint stability is of greater concern for 
the athlete. For example. soccer players who are more experienced display 
more coordinated patterns of muscle activation during cutting maneuvers 
Experienced soccer players, such as Cristiano Ronaldo, display intermuscular 
coordination that allows for stability in speed and changes of direction.
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	 Factors Determining Agility ■ 9
than their less-experienced counterparts do.42 Training involving accelera-
tion, deceleration, and directional changes appears to contribute to improved 
intermuscular coordination and, in turn, better agility performance and a 
lower risk of injury.
Intramuscular coordination relates to an individual muscle’s ability to 
improve motor-unit recruitment, rate coding (sometimes called frequency 
coding), and motor-unit synchronization.39 The greater the number of motor 
units an athlete can recruit at a given time, the greater his ability to produce 
force. Likewise, with rate coding, as the intensity of stimulus increases, the 
rate of peak firing also increases. When these units are recruited quickly and 
in the appropriate sequence, an athlete can express this force over a reduced 
period of time, improving overall potential for speed.39
power
Power, defined as the rate of doing work,14 is an extremely important concept 
in the expression of agility. It may be the most important determinant of 
athletic success.43 Power can be calculated as follows:
Power = Work ÷ Time
In this equation, time means the period in which the work was performed. 
Work can be calculated with this equation:
Work = Force × Distance
Power can also be calculated as follows:
Power = Force × Velocity
In this equation, velocity is speed of movement in a specific direction.
The force-velocity relationship of muscle action shows that as the movement 
velocity increases, the force of muscle output decreases. This phenomenon 
is, of course, disadvantageous for athletes in sports that require both high 
force and high velocity. Examples of movements include starting, stopping, 
and changing direction. To train for this type of movement, athletes should 
focus on improving their ability to exert higher forces at high velocity. In 
turn, this will maximize power.
Keep in mind that athletes cannot effectively train for power by moving the 
body or the resistance slowly during training. As the previous equation sug-
gests, power output can be improved by increasing force output, the velocity 
of movement, or both. Training methods for improving movement velocity 
differ significantly from those used for increasing force output, so a training 
program for agility development must incorporate both. One hypothesis 
suggests that to maximize muscular power, athletes must first maximize 
the magnitude of the force that a muscle is capable of producing (muscular 
10	 ■ Developing Agility and Quickness
strength). Then, they must maximize the rate at which this force is expressed 
(i.e., velocity). Building a base of strength is important for developing move-
ment at higher speeds. This produces a higher output of power.
rate of Force development
Rate of force development is a characteristic of muscle-force output that is 
important for optimal functioning and closely relates to the discussion of 
power. This term is defined as the change in the level of force divided by the 
change in time.25 To illustrate the importance of this concept, consider that it 
takes approximately 0.6 to 0.8 seconds to generate maximal isometric force.56 
However, athletes do not achieve maximum force during high-speed activities. 
In sprinting, for example, the foot contacts the ground for only about 0.1 to 
0.2 seconds.35 Therefore, the time constraints inherent in explosive activities, 
such as sprinting, jumping, throwing, acceleration, and changes of direction, 
dictate that force is developed quickly so that movement can occur rapidly. 
Evan Longoria uses a high rate of force development to create a powerful 
throw quickly.
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	 Factors Determining Agility ■ 11
In these instances, the rate of force development becomes more important 
than the capability for maximum force.51
Part of the process of developing agility includes improving the rate of 
force development of involved musculature so that explosive movements 
can occur at higher forces. In turn, athletes can impart greater forces to the 
ground during foot contact. The rate of muscle activation is thought to be 
the primary factor influencing rate of force development.30 However,
other 
contributing factors may include patterns of motor-unit recruitment,1 fiber-
type composition, and muscle hypertrophy.47 Performing explosive exercises, 
such as plyometrics and Olympic lifts (power cleans, snatches), at the right 
training load and intensity to produce proper speed of movement and force 
output can improve rate of force development.18
Stretch-Shortening Cycle
When required to jump in the air, most people quickly bend the hips, knees, 
and ankles, and then extend those joints. This is because rapidly stretching 
the involved musculotendinous structures (through an eccentric action) cre-
ates greater force and power output in a shorter amount of time during the 
subsequent shortening (concentric) action of the same structures.29, 49 This 
process, known as the stretch-shortening cycle, is involved in most activities 
of daily living. Virtually all athletic skills that require maximum force and 
power output for successful performance use this cycle. Tasks comprised of 
sequential stretch-shortening cycles include winding up to pitch a ball, bend-
ing the arm before pulling a football from the arm of a running back to cause 
a fumble, bending down a few extra inches before getting up from a squat 
position, walking, or any other movement that involves rapid acceleration, 
deceleration, and changes of direction.
Three phases compose the stretch-shortening cycle: eccentric, amortization, 
and concentric (see figure 1.2 on page 12). In the eccentric (stretching) phase, 
the agonist muscles undergo a lengthening action as the athlete initiates the 
movement in the direction opposite to that of the intended movement. This 
phase is extremely important to the effectiveness of the stretch-shortening 
cycle, because this is where the muscle is stretched. Studies suggest that both 
a small magnitude (small range of motion) and high velocity of the stretching 
movement are important for maximizing its contribution to concentric force 
augmentation.5, 32 By moving at smaller ranges of motion with great speed, 
athletes can achieve more recoil in the muscle and produce more force.
The amortization phase may be the most critical phase in the stretch-
shortening cycle. It comprises the transition, or the time between the end of 
the eccentric phase and the beginning of the concentric phase of movement. 
The ability to switch quickly from the eccentric to the concentric phase of the 
stretch-shortening cycle is often termed reactive strength.19 The concentric 
12	 ■ Developing Agility and Quickness
phase of the stretch-shortening cycle represents the time during which force 
application results in motion in the intended direction. In this phase, the 
previous eccentric action created increased force and power output of the 
agonist muscle-tendon units.
The stretch-shortening cycle has been studied for decades. The literature 
attributes the phenomenon to two main mechanisms: one of a neurophysi-
ological nature and the other of a mechanical nature. The neurophysiological 
mechanism relates to the stretching reflex and the activity of the involved 
muscle spindles. When a muscle rapidly stretches (e.g., the rectus femoris and 
gastrocnemius at initial contact in a cutting maneuver), the corresponding 
muscle spindles, which lie parallel to the force-producing muscle fibers, also 
stretch. This results in a monosynaptic reflex, in which the sensory endings 
of the muscle spindles send a signal to the spinal cord about the change in 
muscle length. The spinal cord, in response, sends an excitatory signal to the 
corresponding muscle. These events result in the mechanical mechanism, 
which is a reflexive concentric action of the previously stretched muscle. This 
reflex may also be a protective mechanism against excessive stretching of the 
musculotendinous unit.
Eccentric Concentric
a
Amortization
b c
E4818/NSCA/Fig.1.2/413612/pulled/r1
Figure 1.2 The stretch-shortening cycle in the long jump. The foot touching 
down to the end of the movement is the (a) eccentric phase. The transition from 
the eccentric phase to the concentric phase when no movement occurs is the (b) 
amortization phase. The start of the push off from the foot leaving the surface is 
the (c) concentric phase.
	 Factors Determining Agility ■ 13
At this point, the length of the amortization phase becomes important. The 
stretching reflex occurs less than 50 milliseconds after a rapid stretch.4, 5, 6 
The amortization phase should be kept as short as possible in order to take 
advantage of the potential force increase that results from coupling the stretch-
ing reflex with active, concentric muscle action. In sport terms, visualize a 
boxer getting ready to throw a punch. If the boxer were to pull his arm back 
and hold it there for one or two seconds, the force developed would be greatly 
reduced. If the boxer were to rapidly load the punch, bringing the arm back 
quickly then explosively jabbing it forward (decreased amortization phase), the 
movement would be quicker and he would be able to generate more power.
Improved muscular efficiency also results from the storage of potential 
(elastic) energy in the musculotendinous unit. This involves the stretching of 
the series elastic component (tendon) and, to a lesser extent, parallel elastic 
components (intramuscular fascia) of the musculotendinous unit. Elastic 
Recoiling muscle action increases force and power output, which allows 
athletes, such as Angel McCoughtry, to jump with force and power.
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14	 ■ Developing Agility and Quickness
energy is stored within these components when the muscle is stretched. This 
energy is released shortly after it is stored, either in the form of the tissue 
recoiling to return to its original length or as heat. In sprinting, jumping, and 
cutting maneuvers, the stored energy is used in subsequent force production 
during the propulsion phase.
Once again, the length of the amortization phase has important implications 
here. The elastic energy stored in the series and parallel elastic components 
during the lengthening action only lasts a short time before it dissipates as 
heat. However, if the amortization phase is kept to a minimum, the recoiling 
action of the series and parallel elastic components couple with the active 
concentric muscle action, resulting in increased force and power output. If 
athletes rely exclusively on muscular contraction without prestretching, they 
will need much more energy to do the same tasks, and they would not be 
able to achieve the same level of performance.
The stretch-shortening cycle has a profound influence on the power output 
of explosive movements and on movement efficiency. These characteristics of 
the stretch-shortening cycle may be independent of strength levels in trained 
athletes, but they can be improved by training.2 Therefore, athletes should 
incorporate specific training of the stretch-shortening cycle, also referred to 
as plyometrics, into their programs to maximize speed and agility. Think 
back to our boxer. If he could bring his arm back another inch, gain more 
stretch (like a rubber band), or load, to the muscles and deliver the punch 
in the same amount of time, the stored energy released would help increase 
the force of the punch delivered.
AnthropoMetriC VAriAbleS
Anthropometric variables, such as height, weight, body fat, and length and 
circumference of the limbs and trunk, may play a major role in athletic suc-
cess. For example, a short person with a lower center of gravity and shorter 
limbs can conceivably change direction faster than a taller person with a 
higher center of gravity and longer limbs. Furthermore, assuming that two 
athletes weigh the same amount, it stands to reason that the leaner athlete 
would be able to produce greater force than
the athlete with more body fat. 
This is because the fitter athlete has a greater amount of lean muscle mass.
In some sports, such as basketball, height may be an advantage, even 
though taller people change direction more slowly. A tall basketball player 
may be able to generate more force with his long lever arms. In contrast, a 
shorter wrestler’s height may provide a distinct advantage since it allows him 
to change direction more quickly, due to his leverage and stability. Here, 
shorter lever arms and a lower center of gravity allow the wrestler to execute 
	 Factors Determining Agility ■ 15
movements more quickly. However, the shorter wrestler may produce less 
force than one with longer lever arms.
Many studies have investigated anthropometry to determine its potential as 
a predictor of athletic performance in specific sports, such as gymnastics, vol-
leyball, basketball, rock climbing, swimming, freestyle wrestling, and 10-pin 
bowling.7, 12, 26, 44, 46, 50 These studies found that athletes who perform at high 
levels of competition in their respective sports fit a certain physical profile.
What if an athlete does not fit the profile for his particular sport? Although 
not all athletes may be the next all-pro player in their sport or receive a gold 
medal at the Olympics, they all have the ability to improve a variety of factors 
connected with agility and quickness. Muscle strength and power, improved 
rate of force development, reaction time, and improved technique are all 
components that directly affect overall agility and quickness. Athletes can 
improve these factors with proper training methods and techniques.
One study found that boys with a higher percent of body fat had poorer 
performances in the 40-yard (37 m) dash and in agility tests than their slim-
mer counterparts.3 By simply changing one anthropometric variable, percent 
of body fat, athletes may improve their performance in the 40-yard dash and 
agility tests. If inflexibility in the hamstrings and hip flexors is hindering 
range of motion, then improving mobility in these muscles could positively 
affect performance. For this reason, coaches and athletes should identify 
deficient areas and modify practice and training for the greatest improvement 
on performance.
teChnique
Success in most sports depends on athletes’ ability to rapidly and correctly 
initiate and stop movement in multiple directions while maintaining good 
body control and joint position. Athletes can change directions more effec-
tively by ensuring the body is in the best possible position to produce, reduce, 
transfer, and stabilize both internal and external forces. If any segment of 
the body is out of position, athletes will not be able to achieve optimal agil-
ity performance. Thus, good technique is essential for maximizing agility 
performance and quickness.
Agility is a series of discrete tasks strung together to form what is called a 
serial task. Thus, the athlete must be able to combine the various movement 
patterns discussed in this section in the proper sequence and at the proper 
time while accelerating, decelerating, and transitioning in multiple directions. 
Therefore, athletes should first master individual movement patterns by prac-
ticing each of the skills in a controlled environment. Next, they may combine 
tasks and incorporate them into the specific movement patterns involved in 
16	 ■ Developing Agility and Quickness
a given sport. They can then use specific drills (see chapter 4 for examples) 
to improve footwork and speed in backward and lateral movements.
To produce the movement needed to change directions, athletes need to 
begin in good position. The universal athletic position (shown in figure 1.3) 
is a good beginning stance for a variety of movement patterns. Here, athletes 
slightly bend the knees and hips, slightly lean the torso forward, flatten the 
back, and position the head straight with eyes looking forward.11 Other 
common positions include a staggered stance (see figure 1.4), such as the 
one used by defensive backs in football and a three-point stance (see figure 
1.5) like defensive linemen use. Athletes can incorporate these stances to add 
greater sport specificity to a variety of multidirectional drills.
The same principles of position and body mechanics that are emphasized 
during power movements, such as doing explosive movements or linear speed 
work, are also critical when producing explosive directional changes. Thus, 
the propulsive forces generated through triple extension are vital for optimal 
agility performance. When backpedaling, athletes can achieve propulsion 
with the powerful action of the quadriceps and hip flexors (figure 1.6). The 
arm movement is similar to that used in forward sprinting.
Figure 1.3 The universal athletic position from the (a) front and (b) 
side views.
a b
	 17
Figure 1.4 The staggered stance. Figure 1.5 The three-point stance.
Figure 1.6 Proper body position for backpedaling from the (a) front and 
(b) side views.
a b
18	 ■ Developing Agility and Quickness
In many cases, as athletes attempt to change direction, they pump their 
arms less, allowing the hands to cross the midline of the body or failing to 
swing the arms from the shoulders. Unfortunately, all of these extraneous 
movements may reduce their ability to produce quick directional changes. 
In order to produce force in any direction, athletes should use a proper arm 
swing that originates from the shoulder. Arms bent at approximately 90 
degrees will help them produce greater force and more explosive movements.
The ability to reduce speed is also essential. Figure 1.7 shows the proper 
position for deceleration of a forward movement. Figure 1.8 on page 20 
Figure 1.7 After the (a) last normal stride, the athlete (b, c, d) decelerates by taking abbreviated 
steps until she comes to a (e) full stop.
a cb
d e
	 Factors Determining Agility ■ 19
shows the proper position for both deceleration and acceleration of forward 
and lateral movements. These are the best possible positions for effectively 
producing and reducing speed. Notice during the forward movements (figure 
1.7) that the majority of the athlete’s weight is on the ball of the foot. During 
lateral movements, it is on the medial aspect of the foot (figure 1.8). To 
prepare for any directional change, the angles of the ankle and knee should 
be about or less than 90 degrees, and the hips and center of gravity should 
be in a low position. The foot of the outside leg should remain outside the 
center of mass and the lower leg should point roughly in the direction of the 
desired movement.
The transfer of forces relies on the ability to control the center of mass and 
center of gravity. As the center of gravity shifts away from the center of mass, 
it causes movement. Athletes with great agility can control their center of 
mass and position their bodies in an optimal manner to control their center 
of gravity. If the movement of the center of mass is excessive, causing the 
center of gravity to move too far outside the body, the athlete may lose bal-
ance or even fall. The ability to control center of gravity and center of mass 
allows athletes to transfer force and power more efficiently and to perform 
at higher levels.
Athletes can improve their ability to change directions with balance, body 
control, and minimal loss of speed by widening their base of support and 
lowering their center of gravity. Figure 1.9 on page 22 shows the correct posi-
tion and an example of an incorrect body position during the breakdown of 
a lateral movement. In figure 1.9a, the athlete’s weight is distributed evenly 
on the inside of the foot and the knee is lined up over the ankle. In figure 
1.9b, the majority of the athlete’s weight is on the outside of the foot, and
the 
ankle and knee are in a compromised position over the outside. Furthermore, 
notice in figure 1.9a how the athlete’s shin is roughly pointing in the direction 
of the desired movement. Compare this to figure 1.9b, in which the athlete’s 
shin is pointing in the opposite direction of the desired movement. This angle 
is inappropriate for generating the power necessary for explosive changes of 
direction. Furthermore, it places the joints in a vulnerable position for injury.
When changing direction, some sort of rotation generally must occur 
to transition from one movement pattern to the next.17 For example, when 
transitioning from a forward sprint in one direction to one in the opposite 
direction, many athletes begin by turning the head, immediately followed by 
the shoulders and the trunk. This creates a shift in the body’s center of mass 
that allows the athlete to turn the pelvis and hips in the intended direction 
20
a b
c d
Figure 1.8 (a, b, c) The athlete decelerates by taking abbreviated steps and 
(d) turns laterally while lowering his center of gravity.
	 21
Figure 1.8 (continued) (e, f) While making a lateral change of direction, 
the athlete keeps the center of mass low and points the lower leg in the new 
direction. (g, h) The athlete then accelerates in the new direction.
e f
g h
22	 ■ Developing Agility and Quickness
INCORRECT TECHNIQUE
Figure 1.9 (a) The correct position for changing direction in lateral 
movement. (b) An incorrect body position is less effective and more
likely to cause injury.
a b
of movement.17 Others initiate the rotation at the hip joint of the free leg, 
as shown in figure 1.10. The aim here is for the foot of the free leg to strike 
the ground on the next step, pointing in the intended direction for the next 
movement (see figure 1.11 on page 24). Many athletes attempt to initiate the 
rotation at the hip joint of the stance leg, transitioning the whole body in 
one fluid movement.
Regardless of the technique used, coaches should emphasize several spe-
cific cues to make certain the athlete is in the proper position to transition to 
the next movement with as little wasted motion as possible. Athletes should 
focus on punching the knees of the lead leg and pivoting the hips in the new 
direction. Correct body position produces power angles in the lower body. 
These help produce force and speed of movement. In order to make certain 
that they are fully turning their hips and generating maximal power, athletes 
should imagine that they have a camera at their navel. They should point the 
lens of the camera to take a picture of the direction they wish to go. Another 
cue for proper arm mechanics is to drive the lead elbow back in the direction 
of the planting foot to rotate the upper body and assist with core rotation. 
This action also helps athletes get into proper running form more efficiently.
	 23
Figure 1.10 Transition movement with an open-leg knee drive. This change 
of direction skill teaches the ahtlete to plant and step as part of the change 
of direction motion. The athlete (a) begins to decelerate and (b) plants the 
outside leg, maintaining proper body position to load the muscles for the 
change of direction. The athlete (c) steps with the opposite leg, driving off
the leg to propel in the new direction, and (d) sprints away.
a b
c d
24
Figure 1.11 Transition movement with an opposite-leg knee drive. This 
change of direction skill teaches the athlete to push off as part of the change 
of direction motion. The athlete (a) lowers the center of gravity and loads 
the outside leg while opening the hips and (b) lifting the inside leg to change 
direction. The athlete (c) pushes off with the outside leg, turns hips, and 
gets ready to plant the inside foot with a positive shin angle to move in the 
opposite direction. The athlete (d) sprints away.
a b
c d
	 25
Factors Determining 
Quickness
Chapter 2
Jay Dawes
Jeremy Sheppard
The ability to identify relevant cues and execute the correct correspond-ing movements without delay largely determines an athlete’s success.9 If an athlete misreads or mistimes these cues, it can literally cost a 
goal, a game, or even a championship. Numerous perceptual and decision-
making factors influence a player’s reactive ability, or quickness, which also 
affects agility.
InformaTIon ProcessIng
Before athletes move, they must first identify the need to respond to a situa-
tion. They do this by collecting environmental cues from a variety of sensory 
input systems, such as the auditory, visual, and somatosensory systems.18 For 
example, a running back waits for the quarterback to provide the auditory 
command to signal the start of a play. As he prepares to grab the handoff 
from the quarterback, he collects visual information about the position of 
the defense in an attempt to find a gap to run through. As would-be tacklers 
try to grab him, his somatosensory system gives his central nervous system 
feedback about the manual pressure the opponents are applying to his pads 
and body. Given this information, the player may be able to spin away from 
the attack. This scenario illustrates just one situation where environmental 
cues give athletes important information about their competitive environment.
26	 ■ Developing agility and Quickness
The senses also collect information about specific patterns that indicate a 
particular type of play or an opponent’s position. The athlete must interpret 
this information through perceptual skills to determine the appropriate 
response. Several variables affect the speed at which this information is pro-
cessed, including stimulus clarity, intensity, mode, and experience.17
Stimulus clarity refers to the extent to which the stimulus is well defined 
and clear (i.e., in focus versus out of focus), and stimulus intensity deals with 
the strength or magnitude of the stimulus (loudness, brightness, and so on). 
The greater the clarity or intensity of an environmental stimulus, the faster 
the athlete will be able to process the information.17
The mode, or type of stimulus received also affects the speed at which it is 
detected. The time required to respond to a visual stimulus (approximately 
180 to 200 milliseconds) is greater than the time required to respond to an 
auditory stimulus (approximately 140 to 160 milliseconds). Kinesthetic reac-
tion time is the fastest (averaging 120 to 140 milliseconds).22
Finally, the athlete’s level of experience has a profound effect on overall 
quickness. For example, athletes who are able to read or expect the next play 
based on their opponents’ formation have a greater anticipatory advantage 
than those unable to identify these task-relevant cues. The ability to read 
the opposing player’s actions is largely based on repetition and competitive 
experience over time.
Running backs, such as Adrian Peterson, respond to a variety of environmen-
tal cues, allowing them to elude opponents.
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	 Factors Determining Quickness ■ 27
Coaches should consider this information when developing open drills 
because it provides a better understanding of why athletes take longer to 
respond to some responses than others. (Open, or reactive, drills require 
athletes to respond to a stimulus to complete the drill.) For instance, this 
information shows that in most cases, an athlete will be able to respond to a 
sound more quickly than to a visual stimulus. Further, the type of stimulus 
the coach selects should be directly related to gamelike situations that the 
athlete may experience. For example, a sprinter should respond to a sound 
stimulus, since the same type of cue is used to initiate track events. In contrast, 
a sport-specific stimulus for a defensive lineman in football would involve
movement, since football players look for visual stimuli in competition.
Knowledge of sITuaTIons
The knowledge of specific sport situations helps players react more quickly to 
environmental cues. Cognitive research shows distinct differences between 
experts and nonexperts in visual search strategies.1, 14, 16, 20, 21 This research 
indicates that expert performers use different cues than those with less 
experience do. For instance, an expert base runner may focus on a specific 
body movement by a pitcher (dipping the back leg, lifting the back foot off 
the pitching rubber, or lifting the front foot off the ground) to determine 
when he is going to make a delivery to the plate versus attempting a pickoff. 
Additionally, expert performers can find and focus in on relevant cues more 
quickly than their less experienced counterparts.1, 23
These differences between experts and nonexperts further emphasize 
the need for a highly specific training stimulus in order to improve reactive 
abilities. A generic stimulus, such as a light, is unlikely to be a valid measure 
for gauging performance. If expert performers utilize cues that are specific 
to tasks in a given sport domain, it seems unlikely that a generic stimulus 
would be ideal for improving recognition of a situation. In other words, a 
general reaction demand is unlikely to increase performance for a specific 
demand in a sport. In addition, it may not be a valid method for evaluating 
response-time differences between players of varying performance levels in 
the specific domain of their sport.1, 14, 23
Using the human model for information processing (see figure 2.1 on page 
28), a given stimulus, prior to initiating a response, produces specific mental 
operations based on the subject’s retrieval of stored information from memory. 
The accuracy and speed of this response depends on previously stored 
information that is specific to that situation.8 If the stimulus used in training 
lacks specificity to the sport setting, then the training methods for decreasing 
response time are less valid and less likely to improve sport performance.
28	 ■ Developing agility and Quickness
By collecting and processing information that occurs during sport per-
formance, the athlete may begin to recognize specific types of patterns that 
indicate certain situations. For example, the trajectory or spin of a ball, the 
direction and speed of an opponent, or the opposition’s position are all pos-
sible patterns that an experienced athlete may use to gain advantage over 
those with less experience. In many sports, the better an athlete is at recog-
nizing and interpreting these patterns, the greater his potential for reacting 
quickly and accurately to the given stimulus.17, 18 In a sport like American 
football, specific cues may alert 
the defense whether a passing or 
a running play is about to occur. 
If the defender is able to interpret 
these cues quickly, he is more 
likely to be in the correct posi-
tion to make a necessary play.
This ability to recognize spe-
cific patterns is a skill that ath-
letes can develop through expe-
rience and learning. Thus, both 
the amount and type of practice 
are important. As a player’s 
knowledge of a particular situ-
ation increases and he becomes 
more familiar with the correct 
movement response in relation 
to the stimulus displayed, his 
reaction time or quickness will 
improve. For this reason, during 
the initial stages of learning, 
athletes should perform closed, 
preprogrammed agility drills for 
technique mastery. However, as 
Knowledge of sport situations allows 
an experienced player, such as Caroline 
Wozniacki, to read a ball for a successful 
return.
Response
Mental
operations
specific to 
the stimulus
Stimulus
E4818/Fig F2.1/ 413496/Tammy Page/R1
figure 2.1 Information processing model.
Adapted from R.H. Cox, 2002, Sport psychology: Concepts and applications, 5th ed. (New York: 
McGraw-Hill), 133.
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	 Factors Determining Quickness ■ 29
they perfect technique and gain greater experience in their respective sports, 
open, unplanned quickness drills with appropriate cues may better improve 
their sport performance, due to greater specificity of training.
decIsIon-maKIng sKIlls
Once the athlete has collected information about the environment and the 
situation, he must decide which actions or responses will yield the greatest 
success. Successful decision making requires both speed and precise move-
ment. When the athlete has decided which specific movement to make based 
on information collected from the environment, a message is sent to the motor 
cortex to retrieve the desired movement pattern from memory. When it is 
received, the brain sends a message to the working skeletal muscles through 
the spinal cord to produce the desired movement.22 If athletes choose the 
correct response, their opportunities for success increase exponentially. If 
they choose an incorrect movement, the result can be devastating.
The fake is a popular concept in many sports. In this type of play, an ath-
lete indicates the initial stages of one movement and then quickly performs 
another movement to its completion. Players do this to give the opposition 
incorrect cues so that they cannot respond correctly or quickly enough to 
effectively defend the movement. If opposition players respond to the first 
(deceptive) movement, they will suffer a delay as they attempt to respond to 
the second (actual) movement. In the previous example, if the pitcher appears 
to be about to deliver the baseball to the plate but instead attempts a pickoff, 
this may cause the base runner a momentary delay, causing him to be picked 
off at the current base. If the runner attempts to steal, he may get caught in 
a rundown between bases.
The number of stimuli in the environment and the total number of pos-
sible actions largely determine the athlete’s ability to select an appropriate 
response.17, 18 Typically, reactions are classified as either simple or choice.17 
Simple reaction time refers to the presentation of a stimulus that has only one 
correct response, such as a gun being fired to signal the start of a footrace. 
Choice reactions require an athlete to select an appropriate response to one of 
several unanticipated stimuli.18 Choice reaction time is important for sports 
that require athletes to respond to the movements of other players and to select 
appropriate responses based on these movements. These types of sports tend 
to be chaotic and unpredictable.5 For example, as defenders in soccer follow 
their opponent dribbling downfield, they must watch their opponent’s body 
position, offensive patterns of the opposition, and the location of their own 
teammates in order to take the most appropriate action and to best defend 
against the offensive attack.
30	 ■ Developing agility and Quickness
According to Hick’s law, the amount of time required to prepare a response 
to a stimulus depends on the possible number of responses present.17 Ath-
letes can perform simple reaction tasks more quickly than choice reaction 
tasks because in those situations, only one stimulus is presented and only 
one correct response is possible. As the number of stimuli in the environ-
ment increases, the athlete has a greater number of alternative responses to 
select from in order to perform the correct motor task or skill. As a result, 
the amount of time required to execute a particular movement increases.17
Many experts believe simple reaction time is much harder, if not impos-
sible, to alter through training because it is primarily related to genetics and 
the speed of the central nervous system. However, training and experience 
may significantly improve choice reaction time.18 For this reason, athletes 
must incorporate some form of sport-specific
reactive-agility training into 
their overall strength and conditioning programs to improve their ability to 
respond quickly to multiple stimuli in a chaotic sport environment.
Sports, such as lacrosse, create a chaotic environment in which players must 
react to multiple stimuli.
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	 Factors Determining Quickness ■ 31
anTIcIPaTIon
When athletes can accurately predict an event and organize their movements 
in advance, they can initiate an appropriate response more quickly than if 
they had waited to react to a stimulus. With experience, they gain greater 
knowledge of how long it takes to coordinate their own movements (known 
as effector anticipation) with certain environmental regularities and oppo-
nent tendencies in a given situation (perceptual anticipation). In addition, if 
athletes can predict which play will be used (spatial anticipation) and when 
it will occur (temporal anticipation), they will be able to form an appropriate 
response before the stimulus is presented.
Athletes who anticipate accurately can gain a large competitive advantage 
over their opposition. Anticipation is possible in nearly all sports. For example, 
by watching how an opponent pivots or drops the hips, a rugby player can get 
an idea of what direction an opponent is going or what movement he is trying 
to execute. When a pitcher throws a ball into the dirt, a base runner success-
fully steals a base due to the trajectory of the pitch as the ball was released.
Early studies involving anticipation and reaction time were based on generic 
stimuli and generic athletic responses.7, 13 Some scientists have stressed that 
in order to truly assess and train the visual and recognition skills required in 
athletics, future research about anticipation and reaction time should involve 
a sport-specific presentation.3 Experimental evidence demonstrated that 
generic visual-training approaches to motor learning are most likely ineffective 
because they train perceptual factors that do not influence performance in 
sports or gamelike situations. From these findings, the authors suggest that 
sport-specific protocols that utilize perceptual skills (such as pattern recogni-
tion and anticipation) may be best for establishing the appropriate context, 
or link, to skills in a particular sport.3 High-performance athletes focus on 
anticipatory cues that are directly linked to specific signals displayed by their 
opponents.1, 3, 11 Therefore, at this time, research provides compelling sup-
port for the use of sport-specific scenarios and stimuli in training programs.
As a component of perceptual and decision-making factors, anticipation 
appears to be a trainable quality, since athletes are able to improve these 
skills as they gain more competitive experiences.2, 3, 10, 11, 19 Thus, this area of 
training is worthy of attention. When training anticipation skills, the primary 
goal should be to improve both the accuracy and the speed of responses.
32	 ■ Developing agility and Quickness
For coaches, the previous findings in perceptual and decision-making 
research support using sport-specific scenarios. Scenarios that provide a 
stimulus relevant to the sporting environment may help athletes develop better 
anticipation skills through the refinement of search strategies, response speed 
and accuracy, pattern recognition, and decision-making abilities.
arousal level
Arousal, or an athlete’s overall level of central nervous system excitement and 
activation, plays a significant role in the ability to perform both quickly and 
accurately. The inverted U principle further explains the relationship between 
arousal and performance.4, 18 Figure 2.2 shows the inverted U hypothesis, 
which states that arousal facilitates performance to a certain point. If the 
arousal level is too low or too high, the athlete fails to produce high-level 
performance.18 The zone of optimal functioning, or simply the zone, is the 
level of arousal for the best integration of both the mental and physical pro-
cesses associated with maximal performance.12, 15 It is typified by several 
Through anticipatory cues an experienced hockey player, such as Sydney 
Crosby, can gain a competitive advantage over opponents.
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	 Factors Determining Quickness ■ 33
E4818/NSCA/Fig 2.2/413508/Tammy Page/R1
Low
Optimal
Arousal High
Lo
w
H
ig
h
Pe
rfo
rm
an
ce
factors, including improved automaticity (autopilot) and the increased abil-
ity to identify task-relevant cues and to ignore environmental cues that are 
irrelevant to performance.18
Typically, if athletes’ arousal levels are too low, they may focus too much 
on irrelevant environmental cues. Since their environmental focus may be 
too broad, these perceptual distractions may not allow them to pick up on 
relevant environmental stimuli. Perceptual narrowing, or tunnel vision, may 
also occur as arousal levels continue to rise. This may hinder athletes’ ability 
to identify task-relevant cues, thus increasing reaction time.
Ideally, athletes can identify the optimal level of arousal required to switch 
focus from broad to narrow. For example, when tennis players serve a ball, 
they initially have a broad focus as they scan the court to determine where 
they would like to hit the ball. They would then switch to a narrow focus 
during the serve. Once the serve is complete, they switch back to a broader 
focus to track their opponent and to anticipate where the opponent will return 
the ball. The server may be able to gain anticipatory clues from the position 
of the opponent’s body or the position of the opponent’s racquet when it 
strikes the ball. When the server sees the ball leave the opponent’s racquet, 
he switches back to a narrower focus to concentrate on seeing the ball as it 
comes to his racquet, allowing for an effective reply.
figure 2.2 Inverted U principle.
Reprinted, by permission, from B.D. Hatfield and G.A. Walford, 1987, “Understanding 
anxiety: Implications for sport performance,” National Strength & Conditioning Association 
Journal 9(2): 60-61.
34	 ■ Developing agility and Quickness
For this reason, during practice, athletes may benefit from using open-
skilled, or reactive, games that replicate situations that may be perceived as 
threatening. Examples include an opponent attempting to score a goal or a 
challenge that relates to performing a task more quickly than a competitor 
does. Drills that force players to perform in a competitive situation enhance 
their confidence and skill in adapting to new sport situations. This game-
like environment allows players to adapt their skills and better control their 
arousal levels under the pressure of competition.
In conclusion, athletes’ ability to achieve optimal agility and quickness 
performance depends largely on their perceptual and decision-making skills. 
In order to fully develop these capabilities, athletes must continue to gain 
experience identifying task-relevant cues in their respective sports by training 
in gamelike conditions and using sport-specific training cues and methods 
aimed at improving cognitive abilities and decision-making skills.
	 35
Testing Agility 
and Quickness
ChApTer 3
Jason Jones
Testing agility and quickness involves more than lining up a few cones and grabbing a stopwatch. A proper assessment for the specific demands, distances, and movements involved in a sport should provide 
valuable information for both the coach and athlete. Therefore, administrators 
should carefully select tests for athlete evaluation. Coaches and athletes can 
use the tests and evaluation drills featured in this chapter in several ways:
ff Predicting athletic potential. Coaches often use field tests related to a 
given sport to predict
an athlete’s future ability to successfully perform 
a specific activity or sport.1, 3, 5 Thus, the tests selected to assess athletic 
potential should mimic the specific movement patterns, muscle groups, 
and energy systems required for a particular sport in order to provide 
meaningful information and feedback.
ff Identifying strengths and weaknesses. By determining which change-
of-direction factors and perceptual and decision-making skills need 
improvement, the coach can make better choices about which drills 
should take priority in the athlete’s training program. Further, periodic 
testing may give athletes, coaches, and trainers valuable information as 
to how effective an implemented training program has been.
ff Comparing athletes’ performance levels. Collecting testing data can 
help athletes gain a better understanding of how their performance 
levels compare with those of others. Coaches often use collected data 
to compare athletic performance, evaluate their programs, and track 
progress from one testing period to another and from season to season.
36	 ■ Developing Agility and Quickness
ff Improving motivation and goal setting. Testing can help the coach and 
athlete set specific, measureable, and realistic goals to improve perfor-
mance. Testing athletes regularly provides the coach and athlete with 
valuable information needed to create and modify the training program 
to meet specific goals.1
Just as NFL teams use testing to evaluate players, coaches and athletes 
at all levels can use testing to predict and improve performance.
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	 Testing Agility and Quickness ■ 37
TesT selecTion
When selecting a test to predict athletic performance, coaches must consider 
the validity, reliability, and objectivity of the assessment method. Choosing 
tests with these qualities can help a program succeed. Coaches should also 
make sure the proper tests are being done and should track the outcome of 
every testing session to see if the same parameters are being measured.
Validity
Validity refers to the degree that a test assesses what it intends or claims to 
measure.2 For instance, power production is critical for success in sporting 
events that require jumping, sprinting, throwing, and striking. A success-
ful vertical jump requires an athlete to explosively propel the body upward, 
working a variety of body segments in unison, especially the legs, hips, and 
trunk. Thus, coaches, trainers, and researchers often select this skill when 
assessing anaerobic power of the lower body.4 Sports like basketball, volley-
ball, and football often utilize the vertical jump to predict performance.
reliability
Reliability refers to the repeatability or consistency of a test.2 If a test is truly 
reliable, the results should not greatly differ when multiple trials are per-
formed. Several factors may influence the reliability of a test:
ff Testing surface
ff Clarity of instruction
ff Experience of test administrator
ff Number of trials and practice trials allowed
ff Rest periods between tests
ff Ambient temperature
ff Time of day
ff Motivational factors (i.e., spectators, tester, and teammate encouragement)
ff Nutritional and hydration status
ff Fatigue level
In order for a test to be valid, it must be reliable. However, reliability does 
not ensure that a test is valid. For example, an assessment of body mass 
index may be reliable, but the results may not be as accurate for those who 
are more athletic or muscular.
38	 ■ Developing Agility and Quickness
Objectivity
Objectivity is a form of reliability that refers to how the administrator collects 
test data.2 Objectivity depends on several factors, such as the following:
ff The administrators’ experience and competence in administering the test
ff Inter-rater reliability, or whether multiple testers are able to attain the 
same results
ff Whether standardized testing procedures are followed to ensure that 
all athletes being tested receive consistent instructions and methods
High objectivity occurs when personal bias is alleviated. Multiple admin-
istrators should be able to give the same instructions for a test and obtain 
similar results.
TesTing Process
In order to ensure consistent and accurate results, coaches must take certain 
steps to ensure proper data collection. Establishing protocol before testing 
begins is critical. Everyone involved in the testing process must understand 
what is expected of them as well as the specific methods and procedures to 
be used. When developing a testing protocol, address the items from the fol-
lowing section prior to assessment.
Sequence
After choosing valid, objective, and reliable tests, the administrator must 
decide the testing order. With proper order of testing, the coach can make 
sure to gather accurate data. Things to consider when choosing the testing 
order include the following:
ff Energy demands of the test. Tests involving a display of power should be 
performed before endurance-type tests. Short-duration tests should be 
administered before longer-duration tests. For example, administrators 
should conduct an agility test prior to a test used to determine aerobic 
capacity, such as the 1.5-mile (2.4 km) running test, since fatigue from 
the aerobic test may negatively influence agility performance. Testing 
the energy systems at the right time offers the best results and gives 
the coach a better indication of athletes’ status in terms of performance 
improvement.
ff Number of trials given for each test. Often, multiple trials are a detriment 
to testing athletes because they do not have enough time for proper 
rest and recovery. If athletes perform a test while fatigued, they will 
likely not perform as well as they possibly can. This habit also increases 
	 Testing Agility and Quickness ■ 39
the risk of injury. In general, it is good to offer three practice trials at 
a submaximal speed to allow the athlete to become familiarized with 
each test.
ff Number of athletes participating. In order to maximize the flow of test-
ing, the test administrator must organize the testing protocol to ensure 
athletes can complete all their testing in the allotted amount of time.
ff Number of testing administrators. Depending on the number of athletes 
who are testing, it may be advantageous to have more than one test 
administrator to help maintain accurate and consistent records and 
execute testing protocols as intended. For example, in large groups, 
having at least one administrator to ensure that testing protocol is 
followed accurately and another to time and record scores makes the 
process much more manageable.
ff Equipment needed for each test. Making sure that all assessment mate-
rials are available and ready for the day of testing is paramount for 
executing an efficient session. Coaches can create a quick checklist to 
better organize this process.
ff Recovery time. In order to attain the best score possible on each measure, 
coaches should allow at least three to five minutes between trials. This 
reduces the negative effect of fatigue on the athletes and allows their 
ATP-CP energy systems to fully recover, ensuring that their technique 
does not suffer and that they have enough energy to give their best effort.
equipment
In addition to administrative supplies, such as pencils, clipboards, and forms 
for recording results, the coach must also secure any equipment and safety 
supplies deemed necessary for the testing, including cones, stopwatches, a 
laser timing device, or a first-aid kit.
environment
To ensure safe and accurate testing, the coach must confirm that the area used 
for testing is appropriate. The coach must make sure that the athlete is able 
to safely and effectively perform each test at maximal effort. The following 
are